Two primary characteristics of a filter with respect to frequency response are magnitude response and phase response. The magnitude response of a filter describes how the gain of the filter changes with respect to frequency and the phase response of a filter describes how the phase of the signal changes between the input and output with respect to frequency. In most applications, magnitude response is the most important characteristic of a filter and phase response is not a primary consideration. However, in data communication with keyed carriers, such as in FSK modem transmission, linear phase response is essential to prevent the commonly known bias distortion phenomenom. Previously, others have used an all pass passive LCR or active RC phase equalizer network to linearize the phase response of a filter network. However, such circuits generally require inductors and/or capacitors external to a monolithic integrated circuit. The virtues of using switched capacitor technology as applied to bandpass filters are described in "Exact Design of Switched-Capacitor Bandpass Filters Using Coupled-Biquad Structures" by Martin and Sedra in the IEEE Transactions on Circuits and Systems, Volume CAS-27, No. 6, June 1980, pages 469- 474.